System for driving objects using pressure or traction forces

ABSTRACT

An arrangement for driving objects, such as piles for example, into a receiving surface by pressure or traction forces is herein disclosed. The arrangement includes a piston-cylinder arrangement one end of which is in force transmitting engagement with an object to be driven into a receiving surface and the other end of which is loaded with an anvil means. The cylinder space on one side of the piston is in communication with a supply source of pulsating working medium and the cylinder space on the other side of the piston communicates with an outlet to enable free entry and discharge of the working medium.

United States Patent; 11 1 1111 3,847,230

Blomquist I I Nov. 12, 1974 [54] SYSTEM FOR DRIVING OBJECTS USING1,883,010 10/1932 Sherwood 173/131 X PRESSURE 0 TRACTION FORCES 1758.5758/1956 Wampach 1 173/135 X 3.204534 9/1965 Spannhake 173/112 x [75] Inento Oska Vlve Elon Blomqulst, 3.526 283 9/1970 Horstketter et 11161/535 x Enskede, Sweden [73] Assignee: Stabilator Aktiebolag, Bromma,Primary Examiner-Ernest R. Purser Sweden 42 1222. Ase/trier, F W?!1911211 92! asqb +5 F 9 [22] Filed: Aug. 16, 1972 211 Appl. No.: 280,945[57] ABSTRACT I An arrangement for driving objects, such as piles for 30F example, into a receiving surface by pressure or trac- 1 orelgnApphcanon Pnomy Data t1on forces is herein disclosed. The arrangementin- Aug. 26, 1971 Sweden lO 83l/7l cludes a piston-cylinder arrangementone end of which is in force transmitting engagement withan ob- [52] Clg fi' g ject to be driven into a receiving surface and the other [51] lt Cl Eozd end of which is loaded with an anvil means. The cylin- [58] 3der space on one side of the piston is in communication with a supplysource of pulsating working medium and the cylinder space on the otherside of the piston communicates with an outlet to enable free entry and[56] References Cited discharge of the working medium.

UNITED STATES PATENTS 258,954 6/1882 Tarbell et =11. 173 127 4 Claims 1Drawing Figure SYSTEM FOR DRIVING OBJECTS USING PRESSURE OR TRACTIONFORCES The present invention relates to a system for driving an object,using pressure or tractive forces, and more particularly to a system fordriving an object into dense material and for withdrawing an object fromsuch material, as with ground pile-driving operations for example.

Pile driving, paling and like operations are encumbered with a number ofserious disadvantages. For example, the material is often subjected torough treatment, and in extreme cases is broken. Further, suchoperations create a serious noise problem. Pneumatic hammers are themachines most often used for pile driving operations, especially whendriving steel piles. Other machines used in such operations include drophammers or vibration hammers. The drop hammer is quieter in operationthan the pneumatic hammer, having a noise output of about 95 dB asopposed to 100 dB.

The object of the present invention is to solve the aforementionedproblems and to provide a machine which is more economical, smootherrunning and quieter than known machines and which is more versatile inoperation than said machines. This object is obtained with the machineof the present invention, which is mainly characterized by apiston-cylinder arrangement one end of which is in force transmittingengagement with an object to be driven into a receiving surface and theother end of which is loaded with an anvil means, the cylinder space onone side of the piston being in communication with a supply source ofpulsating working medium and the cylinder space on the other side ofthepiston communicating with a chamber to enable free entry and exit of theworking medium.

The invention will now be described in more detail with reference to theaccompanying drawing, the single FIGURE of which illustratesdiagrammatically a partially cut away vertical view of a machineconstructed in accordance with the invention.

In the illustrated example, the machine is used for driving a pile 1into the ground. The machine com prises a piston-cylinder arrangementhaving a piston 2 arranged for movement relative to a cylinder 3. Thepiston is provided with a piston rod 4 mounted in a guide 5 arranged inone end wall of the cylinder. Arranged on the other end wall of thecylinder is a pad 6 of sound absorbing material. At the lower end of thecylinder there is arranged a conduit 7 which connects with a source ofpressure medium, in the present instance air. Arranged at the top of thecylinder is a conduit 8 which connects the cylinder chamber above thepiston with thesurroundings, in the present instance the atmosphere.

Connected to the conduit 7 is a valve 9 which is guided by a pulsetransmitting means 10. The valve 9 is connected to a compressor ll andto an outlet provided with a silencer 12.

The machine operates in the following manner: The machine is placedopposite the object, c.g. a pile, paling or the like 1 to be driven intoa receiving surface, such as the ground. An anvil 13, having the form ofa hammer for example, is arranged against the piston rod 4,

to provide the desired pulse resistance while the machine is working.Subsequent to starting the compressor 11, the pulse transmitting means,which has an adill justable frequency, controls the valve 9 in a mannersuch that the conduit 7 in placed alternately in comm unication with thecompressor 11 and the outlet 12. In this way pressure changes arecreated beneath the piston which cause the piston the move against theweight of the mass 13, whereafter the pressure is decreased and thepiston is thrown down against the pad'of sound absorbing material.Alternatively, the pressure pulses can be adjusted in a manner to form acushion of air beneath the piston at its bottom position, this cushionof such magnitude as to prevent contact between the piston and the pad6.

In distinction to known methods, the mass applies a constant load, e.g.5 tons, to the pile 1 throughout the entire pile driving operation, viathe piston-cylinder arrangement. In addition, through the pulsating airpressure, the kinetic energy of the mass is used for driving I the pile.The movement of the piston has a frequency determined by the pulsetransmitting means 10 and is suitably variable between 40 and 160 Hz,depending on the nature of the surface into which the pile is to bedriven.

Thus the above arrangement provides a machine with which the pile istreated more gently than with known pile driving machines. Further, incontradistinction to known machines the hammer does not strike directlyagainst the pile, nor is the pile alternately relieved of the loadacting thereon, but that the pile is constantly acted upon by the loadof the hammer. The noise level reached with the machine of the presentinvention lies in the region of dB, which is an appreciable reduction inthe environmental noise nuisance conditions.

When withdrawing, for example, pilot piles from the ground, the pistonrod is hung from a hole in a lifting device and the supply of air underpressure is moved to the connection 8, whereby the pilot pile attachedto the cylinder can be pulled from the ground with small jerks. Althoughthe illustrated machine has been described with reference to air underpressure as the working medium, it will readily be perceived that anysuitable working medium can be used.

Further, although the illustrated machine has been described with thecylinder facing the object to be driven, there is nothing to prevent theposition of the piston-cylinder arrangement from being changed so thatthe piston rod faces the object instead. The ma chine may be arranged towork in an inclined or upright position and is not restricted for use inpile driving operations, but can also be used as a jacking means for ex-I ample.

I claim:

1. An arrangement for driving objects by pressure or traction forces,for instance for pile-driving into the ground, said arrangementcomprising: a piston-cylinder driving means including a piston adaptedto reciprocate in a cylinder; force transmission means comprising a wallof said cylinder at one end of said driving means for maintaining saiddriving means by gravity in permanent force transmitting engagement withan object to be driven; an inertial mass associated with said drivingmeans through said piston for developing a force for permanentgravitational transmission to said object; a cylinder space on the sideof the piston toward said object for communicating with a source ofpulsating supply of driving medium; valve means for opening and closingcommunication between said cylinder space and said source of pulsatingsupply for initially raising said inertial mass against the force ofgravity and away from said object, for then releasing said inertial massto enable the same to faii by gravity in the direction of said object,and for then again raising said inertialmass for another driving cycle,so that the gravitational weight and kinetic energy of said inertialmass combine to drive the associated object when said inertial massmoves in the direction of said object under the influence of gravity andimpacts against said object through said force transmission means; and acylinder space on the other side of the piston for communicating with anoutlet; whereby, in use, the object to be driven is maintainedpermanently loaded by a gravitational force including that of saidinertial mass and is driven by a pulsating force superposed on saidpermanent force, including kinetic energy in said inertial massdeveloped by the gravitational pull on said inertial mass when saidinder adjacent said object is provided with means for absorbing pistonimpact.

4. An arrangement according to claim 1, wherein said source of drivingmedium is connected to an inlet line to the cylinder via a valvecontrolled by a'pulse generator.

1. An arrangement for driving objects by pressure or traction forces,for instance for pile-driving into the ground, said arrangementcomprising: a piston-cylinder driving means including a piston adaptedto reciprocate in a cylinder; force transmission means comprising a wallof said cylinder at one end of said driving means for maintaining saiddriving means by gravity in permanent force transmitting engagement withan object to be driven; an inertial mass associated with said drivingmeans through said piston for developing a force for permanentgravitational transmission to said object; a cylinder space on the sideof the piston toward said object for communicating with a source ofpulsating supply of driving medium; valve means for opening and closingcommunication between said cylinder space and said source of pulsatingsupply for initially raising said inertial mass Against the force ofgravity and away from said object, for then releasing said inertial massto enable the same to fall by gravity in the direction of said object,and for then again raising said inertial mass for another driving cycle,so that the gravitational weight and kinetic energy of said inertialmass combine to drive the associated object when said inertial massmoves in the direction of said object under the influence of gravity andimpacts against said object through said force transmission means; and acylinder space on the other side of the piston for communicating with anoutlet; whereby, in use, the object to be driven is maintainedpermanently loaded by a gravitational force including that of saidinertial mass and is driven by a pulsating force superposed on saidpermanent force, including kinetic energy in said inertial massdeveloped by the gravitational pull on said inertial mass when saidvalve means enables said inertial mass to fall by gravity and impactagainst said object.
 2. An arrangement according to claim 1,characterized in that said source of pulsating supply has the form of acompressed-air compressor connected to an inlet line to the cylinder viaa valve controlled by a pulse transmitting means.
 3. An arrangementaccording to claim 1, characterized in that the inner surface of the endwall of the cylinder adjacent said object is provided with means forabsorbing piston impact.
 4. An arrangement according to claim 1, whereinsaid source of driving medium is connected to an inlet line to thecylinder via a valve controlled by a pulse generator.